Are the Chennai Floods A Signal of Changing Climate?

An ariel view of a submerged Chennai (courtesy: NDTV)

The recent washout that Chennai is nothing short of a catastrophe. It happens on a regular basis in other parts of India; however a Mumbai or Chennai does manage to get our attention in ways we cannot fathom. The severity of the low pressure system has ensured that rain stopped only yesterday, giving the city, the administration and the agencies involved in disaster relief a moment to gasp and bring some semblance of normalcy to people's lives. Of course, the real disaster danger lies once the rain stops and the water begins to subside, as the threat of epidemic manifolds itself in the city. Mind you, so far we have only heard of Chennai - many other cities in Tamil Nadu are faring much worse. Kanchipuram has been completely submerged, and other affected towns are still off-limits to many.

While the rescue and relief operations are going on and the Chennaiites must be commended for rallying together in this time of crisis, a very important question has cropped up due to the timing of this natural disaster with the Climate conference of parties meeting that concluded in Paris only this week. A lot of people are now openly questioning if the events as they unfolded in Chennai and other parts of Tamil Nadu are a signal of a changing climate. The answer is not that simple, because we need a lot of analysis of data that is done by institutes like the Indian Institute of Tropical Meteorology (IITM) in Pune and the Indian Meteorological Department (IMD). But what we do know is what needs to be understood in the right perspective.

What we have had in Tamil Nadu is a one in a hundred year event. In hydrology, a one in a hundred year event essentially refers to the likelihood of this quanta of precipitation (rainfall) to occur in a single day. Now what the climate scientists have been saying is that while this particular event may not be a direct result of climate change, the frequency of occurence of such events may change considerably. Instead of one in hundred years, we may see such rainfall once in fifty years or once in twenty five years.

What such events do tell us however is the fact that a changing climate does pose significant problems of a kind we can only imagine. Fighting climate change will have to be a mix of mitigation and adaptation strategies, and our disaster preparedness will have to spruce itself up considerably to manage and respond early to these dangers as and when they are predicted. Another critical aspect is the building up of climate resilience within cities. Currently, our cities are becoming hotbeds of encroachment over natural watersheds, due to which we see repeated incidents across all major cities in India. Guwahati in Assam has to suffer deluges every year, and yet precious little changes there. This has to be rectified especially if we have to be able to live alongside a changing climate. Much of this of course will happen only if we adopt two way channels of communication between the city residents and the respective administration authority that are far more empowered to do so, and are far more aware of the challenges they need to face. A responsive system thus prepared can certainly go a long way in preparing us for climatic eventualities as and when they arrive.